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Optics Microstructured Optics SMS Design Methods Plastic Optics www.led-professional.com ISSN 1993-890X Review LpR The technology of tomorrow for general lighting applications. Sept/Oct 2008 | Issue 09 Optics Microstructured Optics SMS Design Methods Plastic Optics LED Driver Circuits Display Report Copyright © 2008 Luger Research & LED-professional. All rights reserved. There are over 20 billion light fixtures using incandescent, halogen, Design of LED or fluorescent lamps worldwide. Many of these fixtures are used for directional light applications but are based on lamps that put Optics out light in all directions. The United States Department of Energy (DOE) states that recessed downlights are the most common installed luminaire type in new residential construction. In addition, the DOE reports that downlights using non-reflector lamps are typically only 50% efficient, meaning half the light produced by the lamp is wasted inside the fixture. In contrast, lighting-class LEDs offer efficient, directional light that lasts at least 50,000 hours. Indoor luminaires designed to take advantage of all the benefits of lighting-class LEDs can exceed the efficacy of any incandescent and halogen luminaire. Furthermore, these LEDs match the performance of even the best CFL (compact fluorescent) recessed downlights, while providing a lifetime five to fifty times longer before requiring maintenance. Lastly, this class of LEDs reduces the environmental impact of light (i.e. no mercury, less power-plant pollution, and less landfill waste). Classical LED optics is composed of primary a optics for collimation and a secondary optics, which produces the required irradiance distribution. Efficient elements for primary optics are concentrators, either using total internal reflection or combined refractive/reflective versions. Secondary optics for homogeneous illumination of circular, square or oblong areas, or line foci is based on e.g., the honeycomb condenser principle, microlens arrays, etc. The design goals are high system transmission, minimum loss of etendue, reduction of straylight and a very short system length compared to conventional illumination schemes. Étendue, as a dominant optical design criterion, is the product or multiplication of the area of the emitter surface and the projected solid angle that the rays from the surface diverge into, and the units are mm2-Steradians. This is a three dimensional version of the Lagrange invariant from imaging or conventional lens design. The losses associated with secondary optics vary depending on the particular element used. Typical optical efficiency through each secondary optical element is between 85% and 90%. Traditional optical design is based on ray tracing or aberration theory. Ray tracing is essentially a sampling technique in which data for a few rays are extrapolated to indicate the performance of an entire system. Aberration theory provides a different type of sampling, in which low-order performance coefficients are balanced with high-order performance coefficients to establish overall performance. The September/October 2008 LED professional Review (LpR) issue highlights LED optics and points out how these technologies and methods can be applied in modern LED lighting systems. We would be delighted to receive your feedback about LpR or tell us how we can improve our services. You are also welcome to contribute your own editorials. Yours Sincerely, Siegfried Luger Publisher www.led-professional.com LED professional Review | Sept/Oct 2008 | page 1 Copyright © 2008 Luger Research & LED-professional. All rights reserved. Imprint LED professional Review (LpR) ISSN 1993-890X Publisher Luger Research Institute for Innovation & Technology dep LED professional Rhombergs Fabrik A 6850 Dornbirn, Austria / Europe phone +43 5572 394 489 fax +43 5572 394 698 [email protected] www.led-professional.com LED professional Review (LpR) - Subsription LpR Digital Magazine – free version Publishing Editors • pdf download Siegfried Luger • view only, low resolution Arno Grabher-Meyer Chrystyna Lucyk • private use LpR Digital Magazine – full version Account Manager annual subscription Tiina Himmer • pdf download • pictures and graphs in high Front-page picture resolutions, printable Mixing Rod/ Optical Research Associates • 6 issues (www.opticalres.com); provided by OEC • access to all previous issues • commercial use Copyrights – Luger Research • Euro 78.80 The editors make every reasonable effort to verify the LpR Printed Magazine – annual information published, but Luger Research assumes no subscription responsibility for the validity of any manufacturers, non profit organisations or individuals claims or statements. • 6 issues Luger Research does not assume and hereby disclaims any • Euro 158.40 liability to any person for any loss or damage caused by errors or omissions in the material contained herein, Send E-mail to: regardless of whether such errors result from negligence, [email protected] accident or any other cause whatsoever. You may not copy, Next LpR Issue - Nov/Dec2008 reproduce, republish, download, post, broadcast, transmit, make available to the public, or otherwise use of LED • LED System Simulation and Testing professional Review (LpR) content without the prior written permission from Luger Research – Institute for Innovation & Technology, Austria. www.led-professional.com LED professional Review | Sept/Oct 2008 | page 2 Copyright © 2008 Luger Research & LED-professional. All rights reserved. Content Advertising Index EVERLIGHT p C2 SAMSUNG p 5 Editorial p1 EDISON p 13 Imprint p2 AUSTRIAMICROSYSTEMS p 16 Project News p4 SPHEREOPTICS p 17 Product News p6 JENCOLOR p 17 IP News p12 ALPHA-ONE ELECTRONICS p 17 LED TAIWAN 2009 p 21 LED CHINA 2009 p 27 Application INSTRUMENT SYSTEMS p 40 Progress in LED and OLED Display Technologies ROAL LIVING ENERGY p 51 by M. Nisa Khan, Ph.D., LED Lighting Technologies p14 POWER VECTOR p 51 SOLID STATE LIGHTING ASIA p 52 Optics INTERNATIONAL RECTIFIER p C3 Microstructured Optics for LED Applications TRIDONIC.ATCO p C4 by Arthur Davis, Reflexite Optical Solutions Business p18 Review of SMS Design Methods and Real World Applications by Oliver Dross et al., Light Prescriptions Innovators LLC p33 Plastic Optics Enable LED Lighting Revolution by Tomi Kuntze, LEDIL Oy p41 Driver New Drive Circuit Supports Wide DC Input and Output Range by Bernie Weir, ON Semiconductor p44 Simple and Accurate Constant Current Sensing for Non-Isolated LED Drivers by John S. Lo Giudice, STMicroelectronics p47 Reliability Test of LED Driven by PWM Technique by B. J. Huang et al., National Taiwan University p49 www.led-professional.com LED professional Review | Sept/Oct 2008 | page 3 Copyright © 2008 Luger Research & LED-professional. All rights reserved. Project News Semperlux and Vossloh- Schwabe Illuminate High Water Pumping Station Cologne has been graced with a new landmark: the high-water pumping station in the Bayenthal suburb of the city. The pumping station is already a sight to see during the day thanks to its architectural aesthetic, which Different appearance of the pumping station from a distance view . includes an organically landscaped area that inconspicuously tucks the To suit this specific project, a system was developed that involved structure into the banks of the Rhine. The control building, which was encapsulating standard VS Optoelectronic Flex modules fitted with SMD designed by the architectural company Kasper Kramer (BDA) to feature a LEDs inside the aluminium sections of the metal grid façade. The white, red, contemporary metal grid façade, was kept prominent as the visible face green and blue Flex line modules, each backed with self-adhesive tape, were of the facility. The breathtaking illuminations concept developed by the first precisely trimmed to fit and then fixed within the inside face of the Semperlux lighting technology specialists in Berlin ensures the pumping respective segment. The LED modules were also specifically adapted to station lights up in one of three colours depending on the water level of ensure even light-point spacing and uniform light density over the entire the Rhine. A normal watermark is indicated by white light, rising water building. With the fitting order of the modules having been precisely levels by amber and on reaching the high water mark, the light turns red. calculated by the light engineers at Semperlux, actual installation was The station then begins pumping off the discharge in the reinforced problem-free thanks to the highly flexible nature of the LED modules. conduits. As a result, the citizens of Cologne are not only aware of when Finally, the standard Flex modules were permanently encapsulated within the pumping station is at work, but can also enjoy the eye-catching light the metal sections using a transparent potting material to ensure protection spectacle as a thing of simple beauty. against environmental factors. The indirect LED lighting system works by light hitting the walls of the building and then being reflected to appear as Vossloh-Schwabe Optoelectronic provided the LED technology that made an evenly illuminated surface. In response to the actual water level of the the artistic aspirations of this unique illumination system possible. Project Rhine, a DALI unit triggers the respective light scene and a EUTRAC® DALI decision makers opted for the LED solution for several reasons. Next to low LightComposer®-REG module enables overall system control. As a result, energy consumption, high light output and flexible light control (thanks to both
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